No Boundaries
Biodiversity can emerge even without geographical barriers
It’s commonly thought that organisms need boundaries such as mountains or rivers to split them into different species. But scientists suggest in Nature that biodiversity can emerge spontaneously, without physical barriers to keep species apart.
The team ran computer simulations of mating organisms and found that genetically distinct species appeared even if the environment contained no geographical obstacles. New species emerged at a fairly steady rate, matching observations of North American songbirds and mammal fossils in Kansas. The model also successfully predicted diversity patterns in a range of other animals and plants, including ray-finned fishes, British birds, and Panamanian shrubs.
The behavior is similar to that of traffic jams, which can emerge in the absence of accidents or roadblocks, the authors say. But while organisms didn’t need barriers to form new species, they did need space. That means biodiversity may be difficult to generate if we continue to restrict habitat, says study co-author Yaneer Bar-Yam of the New England Complex Systems Institute. – Roberta Kwok
Source: De Aguiar, M.A.M. et al. 2009. Global patterns of speciation and diversity. Nature DOI: 10.1038/nature08168
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